Conventionally, an ink-jet printer includes an ink head provided with an ink cartridge for supplying ink and, in addition, another ink container to increase the usable ink amount.
For example, conventional ink-jet printers include a relay cartridge connected to an ink head and an additional ink container connected to the relay cartridge. When ink of the relay cartridge is fed to the ink head, ink is supplied to the relay cartridge from the additional ink container. The content of the additional ink container may be larger than the content of the relay cartridge, thus the ink-jet printer can increase the usable amount of ink.
When the additional ink container of the conventional ink-jet printer becomes empty, the additional ink container is exchanged with another additional ink container. However, conventional ink-jet printers include a detecting mechanism which detects the ink amount, and is built into the additional ink container. Therefore, the detecting mechanism needs to be manufactured every time a shape or content of the additional ink container is changed and designing and manufacturing detecting mechanisms has become increasingly costly. Further, some conventional ink-jet printers supply ink to the ink head via a relay cartridge from the additional ink container. When printing, ink flows at all times in the relay cartridge including the detecting mechanism, and the relay cartridge is likely to deteriorate due to extensive use of the relay cartridge over a long period of time.
Hence, providing an ink supply system which increases the usable ink amount and has an ink container provided with a detecting mechanism to prevent wear and deterioration may be advantageous.